From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38B7EC25B48 for ; Fri, 27 Oct 2023 19:29:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231707AbjJ0T3Y (ORCPT ); Fri, 27 Oct 2023 15:29:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230451AbjJ0T3W (ORCPT ); Fri, 27 Oct 2023 15:29:22 -0400 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD517E5 for ; Fri, 27 Oct 2023 12:29:20 -0700 (PDT) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 205A740E018F; Fri, 27 Oct 2023 19:29:19 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id FeXw8_sEkfdh; Fri, 27 Oct 2023 19:29:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1698434956; bh=xbxovbWtvS5eUVU7qTa2e3X1XxpP9O0TH7iacPYNpeg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HqFjx8cwjFdeZKQXtZlqXtDA+1oLEoIhAt0zNaDVoYGFbWWgaKaA1X/TyI/teERfy Nu4zziBp8DwkjLOWSHQtltFppG0zKCWcvUgfY4ztsADPxDC9kFTXSsdRpDOG2a1yyI UuVYsS9R+37+fUxt8IqimJpsdy3/85j1kx3MPc5hZ3xu+VfX2UwDknCoZrBEjpTLOK rROXF0kiH9XPkRytUlTxJ8zCGVgbmevLoujDZqr8CWgj3NHFP3Xn/n9fhYiw7cGYcS K8f0fiVj4+jIIaB5mzBz3I5cW6TrNnYVDoZK27VwsMFnPrLvXp1K1XJKUoR9rC+xC/ ARf0P99Ic/aQDNDG+drt/h4U+xTQOgH5fWfrczAqUeuqOeujj6wRRklxNbrGX2Sd1i d8239NLo3w8mZzo/kcbjrjHvVDFF2mRQSUDw0gPff+RfXSYKtlXHBOE/NboAMGzcj4 d+kSxJTHHCVvVlIpDJl34QaHSHi1pVweuf536cAV8BdGudR9UPksW1m8NaEjNnyCq9 vJIK04IpN8IEDWa+9T0gFhUeurMXVQiikQEyqnb+1Q2A+EZSPcWzWGvRBcznHckscf c2/x10CSiMHVWFbUyaRF/ryuD6vdTweo50Q9LNMYxmCaygxgdCruGd5mZHh+SkytFb OTtTSpWUtMiiSUQqGo18t8ig= Received: from zn.tnic (pd95304da.dip0.t-ipconnect.de [217.83.4.218]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 959E540E0173; Fri, 27 Oct 2023 19:29:12 +0000 (UTC) Date: Fri, 27 Oct 2023 21:29:07 +0200 From: Borislav Petkov To: Peter Zijlstra Cc: X86 ML , Kishon VijayAbraham , LKML Subject: Re: [PATCH 2/2] x86/barrier: Do not serialize MSR accesses on AMD Message-ID: <20231027192907.GSZTwPg8v7NF6+Zn0w@fat_crate.local> References: <20230622095212.20940-1-bp@alien8.de> <20230703125419.GJ4253@hirez.programming.kicks-ass.net> <20230704074631.GAZKPOV/9BfqP0aU8v@fat_crate.local> <20230704090132.GP4253@hirez.programming.kicks-ass.net> <20230704092222.GBZKPkzgdM8rbPe7zA@fat_crate.local> <20231027153327.GKZTvYR3qslaTUjtCT@fat_crate.local> <20231027153458.GMZTvYou1tlK6HD8/Y@fat_crate.local> <20231027185641.GE26550@noisy.programming.kicks-ass.net> <20231027191633.GRZTwMkaiW1nyvnzzO@fat_crate.local> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20231027191633.GRZTwMkaiW1nyvnzzO@fat_crate.local> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 27, 2023 at 09:16:33PM +0200, Borislav Petkov wrote: > Thus the more conservative approach here. And on a second thought, I don't need any of that new stuff - I simply need a synthetic flag which says "MSRs need fencing" and set it on everything but AMD and Hygon. And we've solved this type of issue gazillion times already - why am I reinventing the wheel?! :-\ -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette